NASA's Mars Atmosphere and Volatile Evolution (MAVEN) mission launched aboard a United Launch Alliance Atlas V rocket at 1:28 p.m. from Space Launch Complex 41 at Cape Canaveral Air Force Station on 18 November 2013. The short video shows the launch and the stills show the rocket passing in and out of the clouds.

From a NASA press release on the MAVEN mission:

The Mars Atmosphere and Volatile Evolution, or MAVEN, mission will orbit Mars to explore how the sun may have stripped Mars of most of its atmosphere, turning a planet once possibly habitable to microbial life into a cold and barren desert world. MAVEN will be the first spacecraft mission dedicated to exploring the upper atmosphere of Mars.

Previous missions to Mars have shown us that the atmosphere and climate have changed over time and found evidence of abundant liquid water on the surface in ancient times, though not today. Scientists want to know what happened to the water and where the planet’s thick atmosphere went. The MAVEN mission will study the nature of the red planet’s upper atmosphere, how solar activity contributes to atmospheric loss, and the role that escape of gas from the atmosphere to space has played through time.